bonding and structure

Question 1

ionic bonding

Answer 1

strong electrostatic attraction between oppositely charged ions

Question 2

covalent bond

Answer 2

strong electrostatic attraction between two nuclei and the shared pair of electrons between them

Question 3

electronegativity

Answer 3

the ability of an atom to attract the bonding electrons in a covalent bond

Question 4

metallic bonding

Answer 4

strong electrostatic attraction between metal ions and delocalised electrons

Question 5

Dative covalent bond

Answer 5

Electrostatic force of attraction between two positive nuclei and two electrons from the same atom

Question 6

explain why hydrogen bonding causes ice to be less dense than liquid water

Answer 6

more space between molecules
due to the 3D lattice shape
H bonds are longer than covalent bonds

Question 7

why does Bcl3 have a trigonal planar shape with a bond angle of 120

Answer 7

3 bond pairs 0 lone pairs
bond pairs become more spread apart/max separation
due to repulsion

Question 8

trend in ionic radius of isoelectronic ions along a period

Answer 8

radius increases due to more protons
which increases attraction of nucleus to electrons
( and decreases atomic radius)

Question 9

explain why boiling temperatures increase from chlorine to iodine

Answer 9

more electrons
stronger london forces
more energy required to break intermolecular forces

Question 10

how are carbon atoms arranged in graphene and graphite

Answer 10

hexagonal rings within a layer

Question 11

bond angles in a layer of graphene are

Answer 11

all 120 degrees

Question 12

describe how london forces form between molecules

Answer 12

uneven distribution of electrons
causes an instantaneous dipole
induces a second dipole on another molecule

Question 13

explain why O-H bond are shorter than S-H bonds

Answer 13

sulphur has a larger atomic radius
so more shieling between outer e- and nucleus
less attraction between outer e- and nucleus